diff --git a/ostap/io/root_file.py b/ostap/io/root_file.py
index 814652df..3fdf5c73 100755
--- a/ostap/io/root_file.py
+++ b/ostap/io/root_file.py
@@ -1137,6 +1137,7 @@ def copy_file ( source , destination , progress = True ) :
 ## alias 
 copy_root_file = copy_file
 
+
 # =============================================================================
 ## @class RootFiles
 #  Some specialzation of gheneric class Files for ROOT files
diff --git a/ostap/trees/data_utils.py b/ostap/trees/data_utils.py
index 7c0e39a8..0e0e14f4 100755
--- a/ostap/trees/data_utils.py
+++ b/ostap/trees/data_utils.py
@@ -62,7 +62,6 @@
 # =============================================================================
 if not hasattr ( ROOT.TTree , '__len__' ) :  
     ROOT.TTree. __len__ = lambda s : s.GetEntries()
-
     
 # =============================================================================
 ## @class Data
@@ -104,28 +103,7 @@ def __init__( self                 ,
         ## initialize the  base class 
         RootFiles.__init__( self , files , description  , maxfiles , silent = silent , sorted = sorted , parallel = parallel )
 
-    # =========================================================================
-    ## get a common path (prefix) for all files in collection
-    #  - protocols are ignored 
-    @property 
-    def commonpath ( self ) :
-        """'commonpath': common path (prefix) for all files in collection
-        - protocols are ignored 
-        """
-        from ostap.utils.basic import commonpath 
-        ##
-        if any ( RootFiles.has_protocol ( f ) for f in self.files ) :
-            files = []
-            for f in self.files :
-                files .append ( RootFiles.strip_protocol ( f ) ) 
-        else : files = self.files
-        
-        if not files : return '' 
-
-        cp = commonpath ( files )
-        return cp if os.path.isdir ( cp ) else os.path.dirname ( cp ) 
-    # =========================================================================
-    
+    # =========================================================================    
     @property
     def validate ( self ) :
         """'check' : make check for `TTree`/`TChain` structures
@@ -237,6 +215,9 @@ def table ( self , title = '' , prefix = '' ) :
         nn    = max ( len ( files ) , len ( bad ) ) 
         nfmt  = '%%%dd' % ( math.floor ( math.log10 ( nn ) ) + 1 )
 
+        total_size    = 0
+        total_entries = 0
+        
         from itertools          import chain 
         for i , f in enumerate ( chain ( files , bad ) , start = 1 ) : 
 
@@ -253,6 +234,9 @@ def table ( self , title = '' , prefix = '' ) :
 
                 vv , unit = fsize_unit ( fsize )
                 row.append ( '%3d %s' % ( vv , unit) ) ## file size  
+
+                total_size    += fsize
+                total_entries += entries
                 
             else :
                 
@@ -262,6 +246,16 @@ def table ( self , title = '' , prefix = '' ) :
             row .append ( f   ) 
             rows.append ( row )
 
+        ## summary row
+        from ostap.logger.colorized import infostr 
+        vv , unit  = fsize_unit ( total_size )
+        row   = ''                               , \
+            infostr ( '%d' % total_entries     ) , \
+            infostr ( '%3d %s' % ( vv , unit ) ) , \
+            infostr ( self.commonpath )
+        
+        rows.append ( row )
+
         title = title if title else "Data(chain='%s')" % self.chain_name 
         import ostap.logger.table as T
         return T.table ( rows , title = title , prefix = prefix , alignment = 'rrrw' ) 
@@ -505,6 +499,10 @@ def table ( self , title = '' , prefix = '' ) :
         nn    = max ( len ( files ) , len ( bad ) ) 
         nfmt  = '%%%dd' % ( math.floor ( math.log10 ( nn ) ) + 1 )
 
+        total_entries1 = 0
+        total_entries2 = 0
+        total_size     = 0
+        
         from itertools          import chain 
         for i , f in enumerate ( chain ( files , bad ) , start = 1 ) : 
 
@@ -526,6 +524,10 @@ def table ( self , title = '' , prefix = '' ) :
                 vv , unit = fsize_unit ( fsize ) 
                 row.append ( '%3d %s' % ( vv , unit ) ) ## value 
                 
+                total_size     += fsize
+                total_entries1 += entries1
+                total_entries2 += entries2
+
             else :
                 
                 row.append ( '???' ) ## entries1
@@ -535,6 +537,16 @@ def table ( self , title = '' , prefix = '' ) :
             row .append ( f   ) 
             rows.append ( row )
 
+        ## summary row
+        from ostap.logger.colorized import infostr 
+        vv , unit  = fsize_unit ( total_size )
+        row   = ''                               , \
+            infostr ( '%d' % total_entries1  )   , \
+            infostr ( '%d' % total_entries2  )   , \
+            infostr ( '%3d %s' % ( vv , unit ) ) , \
+            infostr ( self.commonpath ) 
+        rows.append ( row )
+
         title = title if title else "Data2(chani1='%s',chani2='%s')" % ( self.chain1_name , self.chain2_name ) 
         import ostap.logger.table as T
         return T.table ( rows , title = title , prefix = prefix , alignment = 'rrrrw' ) 
diff --git a/ostap/utils/files.py b/ostap/utils/files.py
index bc97c770..3022133a 100644
--- a/ostap/utils/files.py
+++ b/ostap/utils/files.py
@@ -533,13 +533,15 @@ def table ( self , title = 'Files' , prefix = '' ) :
         nn    = max ( len ( files ) , len ( bad ) ) 
         nfmt  = '%%%dd' % ( math.floor ( math.log10 ( nn ) ) + 1 )
 
-        from itertools          import chain 
+        from itertools  import chain
+        total_size =  0 
         for i , f in enumerate ( chain ( files , bad ) , start = 1 ) : 
 
             row   = [ nfmt % i ]
             fsize = self.get_file_size ( f )
             if 0 <= fsize :
-                vv , unit = fsize_unit ( fsize )
+                total_size += fsize 
+                vv , unit   = fsize_unit ( fsize )
                 row.append ( '%3d %s' % ( vv , unit ) ) 
             else : 
                 row.append ( '???' )
@@ -547,6 +549,14 @@ def table ( self , title = 'Files' , prefix = '' ) :
             row .append ( f   ) 
             rows.append ( row )
 
+        ## the last row: summary
+        from ostap.logger.colorized import infostr 
+        vv , unit  = fsize_unit ( total_size  )
+        row   = '' , \
+            infostr ( '%3d %s' % ( vv , unit ) ) , \
+            infostr ( self.commonpath )  
+        rows.append ( row )
+        
         import ostap.logger.table as T
         return T.table ( rows , title = title , prefix = prefix , alignment = 'rrw' )